So basically as an FO no change. the curent "new system" is based on date of line check. So when 767 to airbus happens the guys will go to the fleet their seniority holds. and P.s there is only 18 of them.
and Meph....take your doomsday crap somwhere else. GF is not perfect but 320 never get on widebodies and deathtraps is a bit extreme.